Okay... I'm working on getting all the information/measurements to calculate the CFZ for my setups. However, I'm having difficulty finding an estimate of "seeing" for various conditions. I use Astrospheric to monitor and predict conditions in my area. Is there a rough equivalent for their ratings of excellent, good, average, etc. to seeing arc-seconds? I read some articles about measuring double stars... but wow. I've looked for other sources on how to estimate the seeing in arc-seconds, but am not coming up with anything.